Abstract: The invention relates to a radiofrequency transmission system comprising: means of producing at least one digital signal quantized on N bits; for each of said at least one digital signal, digital processing means including: Sigma-delta filters capable of producing, on the basis of a digital input signal quantized on N bits, a digital output signal quantized on M bits, where M is less than N; downstream from sigma-delta filters, means of repetition over-sampling; and downstream from over-sampling means, convolution means; digital-to-analogue conversion means capable of converting a digital output signal into an analogue signal; and analogue filtering means capable of filtering said analogue signal so as to select a narrow frequency band which includes the second frequency.

Abstract: Radiofrequency transmission system including a digital module producing a first complex digital signal quantised on N bits, a module transforming the first complex digital signal into two second complex digital signals with an identical and constant envelope that are phase-shifted with respect to one another, sigma-delta filters quantising the two second signals into third M bits signals, M being less than N, a digital-to-analogue converter converting the third signals into analogue signals, band-pass filters selectively filtering the analogue signals in a predetermined transmission frequency band, amplifiers amplifying the filtered analogue signals, and filters recombining the amplified analogue signals for transmission.

Abstract: A power amplifier filter for radio-frequency signals having an outphasing type architecture comprising a first stage (2) capable of generating, from an input signal s(t), two signals s1(t), s2(t) having an identical amplitude but phase shifted relative to each other, a second amplifier stage (3) for said signals s1(t), s2(t), and a third recombining stage (4) capable of summing the two signals s?1(t), s?2(t) obtained from second stage (3), characterized in that recombining stage (4) includes an assembly of acoustic wave resonators coupled to each other, some of these resonators referred to as “input resonators” being connected to the outputs of second stage (4) and others of these resonators referred to as “output resonators” being connected to the output terminals of the filter.

Abstract: A power amplifier filter for radio-frequency signals having an outphasing type architecture comprising a first stage (2) capable of generating, from an input signal s(t), two signals s1(t), s2(t) having an identical amplitude but phase shifted relative to each other, a second amplifier stage (3) for said signals s1(t), s2(t), and a third recombining stage (4) capable of summing the two signals s?1(t), s?2(t) obtained from second stage (3), characterized in that recombining stage (4) includes an assembly of acoustic wave resonators coupled to each other, some of these resonators referred to as “input resonators” being connected to the outputs of second stage (4) and others of these resonators referred to as “output resonators” being connected to the output terminals of the filter.

Abstract: The invention relates to a radiofrequency transmission system comprising: means of producing at least one digital signal quantised on N bits; for each of said at least one digital signal, digital processing means including: Sigma-delta filters capable of producing, on the basis of a digital input signal quantised on N bits, a digital output signal quantised on M bits, where M is less than N; downstream from sigma-delta filters, means of repetition over-sampling; and downstream from over-sampling means, convolution means; digital-to-analogue conversion means capable of converting a digital output signal into an analogue signal; and analogue filtering means capable of filtering said analogue signal so as to select a narrow frequency band which includes the second frequency.

Abstract: The invention relates to a radiofrequency transmission system comprising: means of producing a complex digital signal quantised on N bits; means of transforming the complex digital signal into two complex digital signals with an identical and constant envelope that are phase-shifted with respect to one another; a digital processing pathway associated with each of the two complex digital signals with a constant envelope and comprising at least some filtering means of the sigma-delta type for quantising on M bits signals travelling in the processing pathway, M being less than N; digital-to-analogue conversion means for converting the outputs of the digital processing pathways into analogue signals; means of selectively filtering (of the bandpass type) the analogue signals in a predetermined transmission frequency band; means of amplifying the filtered analogue signals; and means of recombining the amplified analogue signals.